Boiling water reactor blade guide and exchange tool

ABSTRACT

A combined blade guide and exchange tool, include a blade guide tool having a lower end and an upper end and a plurality of frame rails supporting a pair of lower collet housings at a lower end of the blade guide tool. A pair of fuel support grapple actuating rods are supported between the plurality of frame rails and have a first end engaging a pair of collets within the pair of lower collet housings and a second end disposed at the upper end of the blade guide tool. A blade exchange tool is releasably mounted to the upper end of the blade guide tool and includes a pair of upper collets for engaging the pair of fuel support grapple actuating rods. The blade exchange tool further including a slider and hook assembly attached to a cable guided by the blade exchange tool and adapted for engaging a control rod.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a divisional of U.S. application Ser. No.16/412,979, filed May 15, 2019, the entire contents of which is herebyincorporated herein by reference.

BACKGROUND Field

The present disclosure relates to a boiling water reactor blade guideand exchange tool.

Description of Related Art

This section provides background information related to the presentdisclosure which is not necessarily prior art.

The control rods in a boiling water reactor contain an absorbentmaterial that when positioned in the reactor core can be used to slowthe fission rate of the nuclear fuel. However, the absorbent material issubject to degradation after extended use. Therefore, it is periodicallynecessary to replace the control rods. In order to remove a control rodfrom its core location, or cell, it is necessary to provide access tothe control rod by removing the fuel and the fuel support associatedwith the control rod to be removed. It is also necessary to disconnectthe control rod from its drive. Tools commonly used to remove the fuelinclude the fuel grapple and a blade guide which supports the controlrod while two of the four fuel bundles are being removed. A control rodunlatching tool is used to disconnect the control rod from its drive.Tools used to remove and/or replace the control rods include a grapplefor lifting the fuel support and a grapple for lifting the control rod.These can be separate tools or their functions combined into one tool.The fuel support and control rod are lifted out of their cell and a newcontrol rod and the same fuel support are placed back in the cell. Thenew control rod is reconnected to the drive without need of tools. Ablade guide is placed in the cell and the control rod is then insertedto allow for fuel installation. Two fuel bundles are then placed in thecells next to the blade guide. The blade guide is then removed and twoadditional fuel bundles are installed in the locations of the vacatedblade guide, to complete the control rod and fuel replacement for thatcell.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

The present disclosure provides a blade guide and exchange tool which iscomprised of two separate tools: the blade guide tool and the bladeexchange tool which, when combined, form the blade guide and exchangetool. The blade guide tool seats on the fuel support and extends upthrough the top guide. The blade guide tool is used to support a controlrod while moving fuel in and out of the cell. In addition to the guidingfeatures, the blade guide tool contains the fuel support grapple that isactuated via a rod that extends from the grapple to the top of the bladeguide tool. The rod is actuated by the blade exchange tool after it ismated to the blade guide tool. The blade guide tool also contains aspring-loaded extension rod, extending the full length of the tool, thatis in line with the core support alignment pin commonly called the 315pin. When the blade guide seats on the fuel support, this extension rodcontacts the 315 pin causing the rod to lift. The lifted rod engages amechanism on the blade exchange tool which opens two air switches. Theopen air switches allow airflow to the fuel support grapple cylinderstherefore allowing for operation of the fuel support grapple. When thefuel support is lifted off the core plate, the spring-loaded extensionrod loses contact with the 315 pin which causes it to move down. Whenthe rod is down, it disengages from the mechanism on the blade exchangetool which causes the valves to close and disables actuation of the fuelsupport grapple.

Initially, two of the four fuel bundles in the cell of the control rodto be replaced are removed using the fuel grapple. The blade guide isthen installed in the removed fuel locations to support the insertedcontrol rod as the remaining two fuel bundles are removed from the cell.The control rod can now be fully retracted to its back-seated position,as there is no fuel remaining in the cell. The blade exchange tool isconnected to an air supply hose and to a hoist via a 12-foot cableattached to the control rod grapple. The blade exchange tool is thenlowered onto the blade guide tool and connected to it. The bladeexchange tool contains a handle latch, fuel support grapple actuators, acontrol rod grapple, and air switches to control airflow to the fuelsupport grapple actuators. When the blade guide and blade exchange toolsare connected and grappled together, the tool is referred to as theblade guide and exchange tool.

When the connection of the two tools is made, the control rod grappleengages the center tubes of the blade guide tool, which act as a guidefor the grapple to keep it centered in the cell as it is loweredapproximately 10 feet to engage the control rod handle. With the bladeguide seated on the fuel support and on the 315 pin, the control rodgrapple is lowered onto the control rod handle. Air is then supplied tothe tool to grapple the control rod and fuel support. The hoist israised to lift the control rod into the tool until the control rodgrapple contacts the underside of the blade guide handle. At this point,raising the hoist further will also lift the blade guide, the exchangetool, and the fuel support. The tool and components are lifted out ofthe cell, via the hoist, and transported to the exchange area. Thecontrol rod is then lowered and seated in the exchange container. Air issupplied to the disengage (or open) side of the exchange tool todisengage the control rod grapple. The control rod grapple air supply(engage and disengage) bypass the air switches and therefore will alwaysoperate regardless of being on or off the 315 pin. The disengage actionwill not actuate the fuel support grapple since the blade guide tool isnot engaged on the 315 pin. When off the 315 pin, the air switch isclosed preventing airflow to the fuel support grapple. At this point,the control rod is seated in the container, the control rod grapple isdisengaged from the control rod handle, and the fuel support is stillgrappled by the tool. The fuel support can now be lifted off the spentcontrol rod, by raising the hoist, and placed onto a new control rodlocated in another storage container. The new control rod is grappled bythe hook, lifted into the tool, and then out of the storage container.The control rod and fuel support are transported back to the core andreinstalled in the cell. After the fuel support and control rod areseated in the guide tube and the fuel support has engaged the 315 pin,both the fuel support and control rod can be released. The bladeexchange tool can be lifted off the blade guide tool. The blade guidetool remains to allow for blade insertion and loading of two fuelbundles into the cell. After this step, the blade guide is removed viathe fuel grapple, and two additional fuel bundles can be loaded in itsplace.

According to an aspect of the present disclosure, a combined blade guideand exchange tool includes a blade guide tool having a lower end and anupper end and a plurality of frame rails supporting a pair of collethousings at a lower end of the blade guide tool. A pair of fuel supportgrapple actuating rods are supported between the plurality of framerails and have a first end engaging a pair of collets within the pair ofcollet housings and a second end disposed at the upper end of the bladeguide tool. A blade exchange tool is releasably mounted to the upper endof the blade guide tool and includes a pair of upper collets forengaging the pair of fuel support grapple actuating rods. The bladeexchange tool further includes a trolley and hook assembly attached to acable guided by the blade exchange tool and adapted for engaging andlifting a control rod.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a perspective view of a blade guide and exchange toolassembled on a fuel support and having a control rod fully retractedaccording to the principles of the present disclosure;

FIG. 2 is a perspective view of the blade guide and exchange toolassembled on a fuel support and having the control rod fully extended;

FIG. 3A is a close-up perspective view of the bottom of the blade guideand exchange tool assembled on a fuel support;

FIG. 3B is a close-up perspective view of the top of the blade guide andexchange tool;

FIG. 4A is a close-up perspective view of the top of the blade guide andexchange tool with the hook being engaged to the handle of the controlrod in its extended position;

FIG. 4B is a close-up perspective view of the bottom of the blade guideand exchange tool with the hook being engaged to the handle of thecontrol rod in its retracted position;

FIG. 5 is a perspective view of the blade guide tool according to theprinciples of the present disclosure;

FIG. 6 is a partially cutaway view of the top of the blade guide toolaccording to the principles of the present disclosure;

FIG. 7 is a partially cutaway view of the top of the blade guide toolaccording to the principles of the present disclosure with the coresupport pin actuating rod shown in a retracted position;

FIG. 8 is a front perspective view of the blade exchange tool accordingto the principles of present disclosure;

FIG. 9 is a rear perspective view of the blade exchange tool shown inFIG. 8 ;

FIG. 10 is a front plan view of the blade exchange tool shown in FIG. 8;

FIG. 11 is a top perspective view showing the blade exchange tool beingassembled to the blade guide tool according to the principles of thepresent disclosure;

FIG. 12 is a side perspective view showing the blade exchange tool beingassembled to the blade guide tool according to the principles of thepresent disclosure;

FIG. 13 is a side perspective view showing the blade exchange tool fullyassembled to the blade guide tool according to the principles of thepresent disclosure;

FIG. 14 is a top perspective view showing the clearance for the sliderof the blade exchange tool being assembled to the blade guide toolaccording to the principles of the present disclosure;

FIG. 15 is a side plan view of the top of the blade guide and exchangetool;

FIG. 16 is a detailed view of the air switch actuator assembly and theair switch of the blade guide and exchange tool;

FIG. 17 is a partial cutaway view of the collet housing and colletassembly used for engaging the fuel support;

FIG. 18 is a partial cutaway view of the collet housing and colletassembly during an engagement of the fuel support;

FIG. 19 is a partial cutaway view of the collet housing and colletassembly after full engagement of the fuel support; and

FIG. 20 is a cross-sectional view of the upper collet housing accordingto the principles of the present disclosure.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto,” “directly connected to,” or “directly coupled to” another elementor layer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer, or section from another region,layer, or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer, or section discussed below could be termed a second element,component, region, layer, or section without departing from theteachings of the example embodiments.

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,”“lower,” “above,” “upper,” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

With reference to FIGS. 1-4 , a blade guide and exchange tool 10 isshown including a blade guide tool 12 and a blade exchange tool 14removably assembled to the blade guide tool 12. In FIGS. 1, 2, 3A and4B, a base 12 a of the blade guide 12 is shown engaged with a fuelsupport 16 which is disposed next to a core support 18. As best shown inFIGS. 3A, 3B, a control rod 20 includes a plurality of blades 22A-22Dformed in a cruciform shape and extending through a cruciform passage 24in the fuel support 16. As is known in the art, the control rod 20contains an absorbent material that when positioned in the reactor corecan be used to slow the fission rate of the nuclear fuel. The fuelsupport 16 includes four pockets 26 each for receiving the base of afuel bundle (not shown).

The base 12 a of the blade guide tool 12 includes a pair of collethousings 30 which each house a collet assembly 32, best shown in FIGS.17-19 . The pair of collet housings 30 are connected to a pair of outerframe rails 34 a, 34 b and a pair of inner frame rails 36 a, 36 b. A topplate 38 is attached to the tops of the outer frame rails 34 a, 34 b andthe inner frame rails 36 a, 36 b. A plurality of brace plates 40 aredisposed between corresponding ones of the outer frame rails 34 a, 34 band the inner frame rails 36 a, 36 b. The brace plates 40 each include aguide hole 42 extending there through. A pair of fuel support grappleactuating rods 44 extend through each of the guide holes 42 of the braceplates 40 and have a bottom end that engages a collet assembly 32 withinthe pair of collet housings 30 and have a top end that is disposed in acorresponding guide housing 46 extending below the top plate 38. Aspring 47 is disposed in the guide housing 46 for biasing the fuelsupport grapple actuating rods 44 in an upward direction.

A core support pin actuating rod 48 is disposed within, and extendsalong a length of one of the outer frame rails 34 a. The core supportpin actuating rod 48 has a lower end that is guided within a guidehousing 50 and engaged by a core support pin 52 (best shown in FIGS.17-19 ) when the blade guide tool 12 is properly seated in the fuelsupport 16. The core support pin 52 extends upward from the core support18 and when engaged by the core support pin actuating rod 48, causes thecore support pin actuating rod 48 to move upward in order to causeactivation of an air switch actuator assembly 54 of the blade exchangetool 14, as will be described in further detail herein.

As best shown in FIG. 8 , the blade exchange tool 14 includes a baseplate 56 to which the air switch actuator assembly 54 is mounted alongwith a pair of upper collet housings 58. A pair of air cylinders 60 aremounted on each of the collet housings 58. The baseplate 56 includes anopening 62 (best shown in FIG. 8 ) therein for receiving a U-shapedhandle 64 extending from the top plate 38 of the blade guide tool 12.The upper collet housings 58 are each mounted in additional holes in thebaseplate 56 and extend below the baseplate 56 and are adapted to bereceived in corresponding holes 66 (as shown in FIGS. 11-13 ) in the topplate 38 of the blade guide tool 12.

As shown in FIGS. 8 and 9 , a mounting structure 68 is mounted to thebaseplate 56 adjacent to the opening 62 and includes a handle engagementbracket 70 mounted thereto. The handle engagement bracket 70 includes aslot 72 for receiving the handle 64 of the blade guide tool 12 and alsodefines a cable guide 74 for receiving and guiding a cable 76 therethrough. The cable 76 is attached to a slider 80 which supports anengagement hook 82 and pneumatic hook actuator assembly 84. The slider80 is engageable with the inner rails 36 a, 36 b to traverse along thelength of the inner rails 36 a, 36 b. The slider 80 can be lowered bythe cable 76 along the inner rails 36 a, 36 b and can bring the hook 82into engagement with an upper handle 20A of the control rod 20. The hook82 can be pneumatically engaged by the cylinder of the hook actuatorassembly 84 and the cable 76 can be utilized to raise the control rod20. As best shown in FIG. 9 , a pair of downwardly protruding guideplates 88 extend below the baseplate 56 of the blade exchange tool 14 toguide the slider 80 into its transition between the inner rails 36 a, 36b.

As best shown in the partially cutaway view of FIG. 10 , each of theupper collet housings 58 include an upper collet 90 disposed within thehousing and engaged with the air cylinder 60 for activation. The uppercollets 90 are engageable with the upper end of the fuel support grappleactuator rods 44 to latch onto the actuating rods 44 and to press theactuating rods 44 downward into the lower collet housings 30 as shownsequentially in FIGS. 17-19 , for engaging the lower collets 32 tospread laterally outward to engage an inwardly extending lip 92surrounding the fuel bundle pockets 26 of the fuel support 16 by a hookportion 94 on the ends of each collet section 32. Accordingly, the lowercollets 32 are engageable with the fuel support 16 in order to lift thefuel support 16 out of the core along with the control rod 20.

As mentioned above, the core support 18 includes a core support pin 52which causes the core support pin actuating rod 48 to move upward inorder to cause activation of an air switch actuator assembly 54 of theblade exchange tool 14. The air switch actuator assembly 54 includes ahousing 100 which supports a core support pin flag 102. The core supportpin flag 102 is engaged with an upper end of the core support pinactuating rod 48 which presses the core support pin flag 102 upward whenthe core support pin actuating rod 48 is pushed upward by engagementwith the core support pin 52 when the blade guide tool is properlyengaged with the fuel support 16. As shown in FIG. 16 , an air switch104 is mounted to the air switch actuator assembly 54 and includes a camfollower 106 and switch arm 107 engaged with a cam surface 108 on thecore support pin flag 102. As the core support pin flag 102 is pushedupward, the switch arm 107 of the air switch 104 is actuated to allowdelivery of pneumatic air pressure to a latch that latches the bladeexchange tool 14 to the blade guide tool 12 and, when not actuated, toprevent delivery of pneumatic air pressure to a release side of thecollet air cylinders 60. As best shown in FIG. 10 , a blade guide hook110 is mounted on the mounting structure 68 for securing the handleengagement bracket 70 to the handle 64 of the blade guide tool 12 toprevent separation there from. The blade guide hook 110 can be actuatedmanually or by a pneumatic actuator.

When the cable 76 is lowered to allow the slider 80 and hook 82 to bepositioned relative to the handle 20 a of the core 20, the cylinder ofthe hook actuator assembly 84 can be activated to engage the hook 82 tothe handle 20 a.

During operation, the blade guide and exchange tool 10 is comprised oftwo separate tools, the blade guide tool 12 and the blade exchange tool14 which when combined, form the blade guide and exchange tool 10. Withtwo of the fuel bundles removed, the blade guide tool 12 seats on thefuel support 16 and extends up through a top guide of a cell. The bladeguide tool 12 is used to support a control rod 20 while moving fuel inand out of the cell. In addition to the guiding features, the bladeguide tool 12 contains the fuel support grapple lower collets 32 thatare actuated via the actuating rods 44 that extends from the collets 32to the top of the blade guide tool 12. The actuating rods 44 areactuated by the blade exchange tool 14 after it is mated to the bladeguide tool 12. The blade guide tool 12 also contains a spring-loaded pinactuating rod 48 that is in line with the core support alignment pin 52and extends the full length of the blade guide tool 12. The pinactuating rod 48 is used to operate the air switch 104 of the bladeexchange tool 14 to control airflow to the fuel support grapple collets32 when the pin actuating rod 48 is either engaged, or not engaged, onthe alignment pin 52.

The blade guide tool 12 is installed first into the cell of the controlrod 20 to be removed. The blade guide tool 12 supports the insertedcontrol rod 20 as the remaining two fuel bundles are removed from thecell and supports the control rod 20 as it is fully retracted to itsback-seated position. The blade exchange tool 14 is connected to an airsupply hose and to a hoist via a 12-foot cable attached to the controlrod grapple 20 a. The blade exchange tool 14 is then lowered onto theblade guide tool 12. The blade exchange tool 14 contains a connectinghook 110 to join the blade guide tool 12 and the blade exchange tools 14together, and a pair of air actuators 60 for the fuel support grapplecollets 32. When the blade guide tool 12 and the blade exchange tool 14are connected and grappled together, the tool 10 is referred to as theblade guide and exchange tool 10. After connection of the two tools 12,14, the upper collets 58 lock onto the fuel support grapple actuatingrods 44 of the blade guide tool 12 to guide the blade exchange tool 14as it is lowered onto the control rod handle 20 a. Air is supplied tothe tool 14 to grapple the control rod 20 via hook 82 and fuel support16 via the lower collets 32. The control rod 20 is then lifted into thetool 10 until the control rod slider 80 contacts the top and of theblade guide and exchange tool 10 at which point the blade guide andexchange tool 10, along with the control rod 20 and fuel support 16 arealso lifted.

The tool 10, control rod 20, and fuel support 16 are removed from thecell and transported to the exchange area. The control rod 20 is loweredand seated in an exchange container. The fuel support grapple collets 32will not release since the tool 10 is not engaged with the core supportalignment pin 52 and therefore the air switch 104 is closed preventingairflow to the retract side of the fuel support grapple collets 32. Thefuel support 16 can now be lifted off the spent control rod 20 andplaced onto a new control rod 20 located in another storage container.The new control rod 20 is grappled by the hook 82, lifted into the tool10, and then reinstalled in the cell. After the fuel support 16 andcontrol rod 20 are seated in the guide tube, both are released and theblade exchange tool 14 can be lifted off the blade guide tool 12. Theblade guide tool 12 remains to allow for blade insertion and loading oftwo fuel bundles. The core support pin actuating rod 48 is engaged withthe core support pin 52 to allow the air release to the air cylinders 60of the upper collets 90 via the air switch actuator assembly 54.Accordingly, the blade guide tool 12 is then removed via release of thecollets 32 and so additional fuel bundles can be loaded.

With the present disclosure, the blade guide function and the controlrod exchange function are combined into one tool therefore two in-corealteration steps, the need to remove and reinstall a blade guide.

The present disclosure also provides verification checks (315 pinengagement and fuel support grappling) that are located at the top ofthe tool (as opposed to other tools which have verifications at thebottom of the tool) and can easily be viewed and verified by anunderwater camera. The ease of verification checks saves considerabletime in the overall exchange process.

The grid guide is a separate tool used with other control rod exchangetools but is not needed with the blade guide and exchange tool of thepresent disclosure, as the blade guide portion of the tool serves thegrid guide function. This eliminates setup and installation of this tooland therefore saves time and radiation exposure to the worker.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

The invention claimed is:
 1. A method of removing a control rod and fuelsupport from a cell of a boiling water reactor, comprising: insertinginto the cell a blade guide tool having a pair of collet housings at alower end of the blade guide tool so that the pair of collet housingsare received in respective fuel bundle pockets in the fuel support, theblade guide tool including a pair of fuel support grapple actuating rodseach including a first end engaging a respective one of a pair of lowercollets within the pair of collet housings and having a second enddisposed at an upper end of the blade guide tool; assembling a bladeexchange tool to the upper end of the blade guide tool, the bladeexchange tool including a pair of upper collets for engaging the pair offuel support grapple actuating rods, the blade exchange tool furtherincluding a slider and hook assembly attached to a cable guided by theblade exchange tool; actuating the pair of upper collets to engage thepair of lower collets via advancement of the fuel support grappleactuating rods and causing the pair of lower collets to engage the fuelbundle pockets in the fuel support; and engaging the hook assembly to acontrol rod and lifting the blade guide tool, the blade exchange tool,the control rod and the fuel support from the cell.
 2. The methodaccording to claim 1, wherein a pair of air cylinders are connected torespective ones of the pair of upper collets and the actuating the pairof upper collets includes activation of the pair of air cylinders. 3.The method according to claim 2, wherein the inserting includes engaginga fuel support pin actuating rod to a pin on a core support, the fuelsupport pin actuating rod is engageable by an air switch actuatingassembly of the blade exchange tool, the air switch actuating assemblybeing engageable with an air switch of the blade exchange tool, the airswitch being activated to prevent airflow to a retract side of the aircylinders of the pair of upper collets.
 4. The method according to claim1, wherein the slider and hook assembly includes a hook actuatorcylinder and the engaging the hook assembly to a control rod includesactuating the hook actuator cylinder.
 5. The method according to claim1, wherein the assembling includes the blade exchange tool releasablyconnecting the blade exchange tool to the blade guide tool.
 6. Themethod according to claim 1, wherein the assembling includes the bladeguide tool having a top plate at the upper end of the blade guide andthe blade exchange tool includes a base plate that is supported on topof the top plate when the blade exchange tool is engaged with the bladeguide tool.
 7. The method according to claim 1, wherein the pair ofupper collets are each disposed within a respective upper collethousing.